Single chip imaging devices such as charge coupled devices (CCD) and CMOS type image sensors can operate using small power sources and relatively little energy. Such imaging devices are implemented in applications as diverse as star tracking applications and imaging the inside of the gastrointestinal tract.
For example, U.S. Pat. No. 5,604,531, assigned to the common assignee of the present invention, describes a swallowable capsule for imaging the full length of the gastrointestinal tract The swallowable capsule includes a camera system, an optical system for imaging an area of interest onto the camera system and a transmitter which transmits the video output of the camera system
In some instances the imaging devices are inaccessible to an operator at the appropriate time for activation, such as for reasons of sterility, and must be activated by remote control such as by IR or radio.
A method for activating a battery, though not a battery of an imaging device, is exemplified in PED Inc's swallowable temperature pill. PED Inc. advertises a swallowable temperature pill for tracking core body temperature. The temperature pill is powered by a silver oxide battery. The battery is kept turned off during storage by a small magnet that is taped to the pill package and is activated by removing this magnet.